Lifting clamps for hoisting lines



P 1956 N. c. RUSHING 7 2,761,725

LIFTING CLAMPS FOR HOISTING LINES Filed Feb. 6, 1952 INVENTOR. NATHAN C. RUSH] NG ATTORNEY United States Patent 2,761,725 LIFTING CLAMPS FOR HOISTING LINES Nathan C. Rushing, Beaverton, Oreg. Application February 6, 1952, Serial No. 270,119 1 Claim. (Cl. 294-78) My invention relates to lifting clamps and is particularly adapted to be used in connection with hoisting lines for handling cargo and the like.

The primary object of my new and improved clamp for hoisting lines is to be able to use chokers in the form of steel straps around and under the cargo. These chokers or straps in many cases remaining under the cargo, the said straps being easily attached to my new and improved lifting clamp.

By leaving the straps under the cargo much more cargo can be stored, due to the fact that the same does not have to be spaced above the decks or floors in order to pick the same up, as is the case where other kinds of lifting apparatus is used where the same must be slipped under the cargo and above the floor surface.

Another object of my new and improved clamp is that the weight of the cargo tightens the clamp in regards to the lifting straps.

A further object of my invention is that the clamp can be locked to the chokers or straps and released by remote control, as by the operator of the hoist.

These and other incidental objects will be apparent in the drawings, specification and claim.

Referring to the drawings:

Figure 1 is a perspective view of one preferred form of my new and improved lifting clamp.

Figure 2 is a longitudinal sectional view of Figure 1, illustrating how the lifting straps or chokers are secured and gripped by the clamp.

Figure 3 illustrates how the straps are brought under the cargo and gripped by my new and improved hoisting clamp.

Figure 4 is an end sectional view, taken on line 4-4 1 of Figure 3.

Figure 5 is an end view, illustrating how the lifting straps pass under the cargo permitting the cargo to rest flat on the floor and how the straps are connected to my new and improved lifting clamp.

Figure 6 is a sectional view of another preferred form of my lifting clamp employing a hydraulic cylinder for locking or unlocking the clamp.

Figure 7 is a side view, taken on line 77 of Figure 6, partially broken away for convenience of illustration.

Referring more specifically to the drawings:

My new and improved lifting clamp in the form illustrated in Figures 1 and 2 consist of a hollow body I, having side walls 2 and 3, a front wall 4 and a rear wall 5. The front wall 4 is arranged at an angle to the rear wall 5, as best illustrated in Figure 2, the upper part of the wall being relatively close to the rear wall 5 and its lower portion spaced a greater distance therefrom.

Working longitudinally within the body member 1 is a wedge 6 having a loop of cable 7 secured therein at 8 by any well known method now being used, or there could be a loop formed as part of the upper end of the wedge.

A cross pin 9 is journalled within the lower ends of the side walls 2 and 3 and is adapted to pass through a loop 10 formed on the lifting strap 11 on one of its ends. The opposite end 12 of the lifting strap is passed in front of the rear wall 5 from the bottom adjacent the wedge 6, which would be lowered a suflicient distance to permit the strap to pass between the wedge and the face of the rear wall 5.

When the hoisting cable 13 is attached to the loop 7 of Fatented Sept. 4,

the clamp by way of the usual hook 14, it will raise th Wedge 6 within the body 1 of the clamp, the Wedge will then be forced against the lifting strap 11 by the inclined front wall 4 of the clamp. The heavier the load the tighter will be the clamping effect on the end 12 of the lifting strap. The face of the rear wall 5 is roughened as at 15 to further grip the lifting strap.

The cross pin 9 is easily removable so that the lifting straps can be left under the cargo or when the wedge 6 is released from their opposite ends 12. The straps can be released from the clamp and the straps pulled from under the cargo if so desired by the pin 9 and the loop 10.

Referring to Figures 3 and 4, the lifting straps 11 can be securely attached around the cargo, as for instance the pipes 16 by way of a suitable clip 17, then my new and improved clamp can be secured to the ends 18 of the lifting straps, the straps being secured around the cargo at the point of origin. The straps not only serve as a binder for the cargo, but a means of being able to lift the cargo by my new and improved clamp.

Referring to Figures 4, 6 and 7, I have illustrated another preferred form of my lifting clamp. The body 1 of the clamp consists of two walls 19 and 20 formed at an angle to the center line of the clamp and adapted to receive a double wedge 21. This wedge is positively operated longitudinally of the clamp by the fluid cylinder 22, the cylinder forming part of the removable base 23, which is bolted to the downwardly extending legs 24.

The object of the removable base is to be able to remove the wedge from the bottom of the clamp. With this type of wedge, referring to Figure 4, both ends 18 of the lifting straps are wedged simultaneously within the lifting clamp. The weight of the'cargo will cause the Wedge 21 to clamp the straps within the clamp supporting the load, but at the same time the fluid cylinder 22 can assist in this wedging effect being controlled at a remote station, as for instance by the operator of the hoisting mechanism.

With this type of clamp, the lifting straps can be released from the lifting clamp remotely by the fluid cylinder pulling the wedge downwardly and away from the ends of the straps, allowing them to be removed from the clamp.

There are many applications of my lifting clamp where it is desirable to operate the same from a remote station. My clamps can be used either singularly or in multiples, depending upon the type of cargo being handled.

What I claim is:

A lifting clamp comprising a hollow tubular body of rectangular cross-section and open at both ends, two opposite side walls of said body being inclined upwardly toward each other to provide a smaller top end opening than the bottom end opening, a wedge member of a cross section conforming to the interior of said body and having an inclined surface corresponding to said inclined walls, a supporting loop fixed to the top of said wedge for connection to hoisting apparatus, an open frame depending from the hollow tubular body, a motor supported by and between the frame including a cylinder, and a piston rod, the free end of the rod being connected to the bottom of the Wedge, in combination with a looped steel lifting strap, having its ends passed between opposite sides of the wedge and the tubular body.

References Cited in the file of this patent UNITED STATES PATENTS 1,114,235 De Carteret Oct. 20, 1914 1,442,862 Curtis Jan. 23, 1923 2,349,520 Ripley May 23, 1944 2,416,150 Botts Feb. 18, 1947 FOREIGN PATENTS 108,982 England Aug. 30, 1917 

